Started on Mycophenalate last week and was prepared for side effects but I feel awful

I am nauseated which I expected but I am also really tired, have sore joints and can't get warm. How do I know which of the above 3 it is... or does it not really matter? Do I just put it under the great umbrella that is Lupus? Does it take a while to get used to Myco?

Started on 250mg twice a day and have a schedule to increase it slowly. I'm inclined to think it is a flare as the nausea didn't kick until a few days after I started them and the more it goes on the more it feels like a flare. Probably a co-incicidence it began at the same time as the Myco then, and like you say.... it's BLOODY cold!!